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    welcome to <mark>html</mark>
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    同学们，<time datetime="2022-5-20">2022-5-20</time>情人节放假一天！
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    <details>
        <summary>HTML</summary>
        <p>Hyper Text Markup Language</p>
        <p>由各种标签组成，用来制作网页，告诉浏览器该如何显示页面</p>
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    <meter max="100" min="0" value="80" high="60" low="20" optimum="30"></meter>
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